This invention relates to machines for conveying materials. More particularly it relates to hopper feed elevators.
Hopper feed elevators are commonly used in factories where there are requirements for removing parts from a storage facility and for segregating parts into smaller groups for an assembly or other operation. A large storage bin, or hopper, containing a large number of parts is situated on the factory floor with a somewhat vertically oriented endless belt or chain having a plurality of cleats thereon passing through the hopper. The moving cleats elevate the parts to a position above the storage hopper. The parts are dumped on a horizontal conveyor, orientor, furnace, or the like in small evenly dispersed amounts as the cleats pass over a roller at the top of the apparatus.
Quite often the parts are rather small pieces such as, for example, machine screws. One of the most common problems which occur with hopper feeder elevators is jamming of the apparatus at and/or below the place where the cleats enter the storage hopper at the bottom of the hopper, particularly when elevating small or thin parts. Often the small parts will become wedged between a cleat and the interface at the opening at the bottom of the hopper.
Two examples of prior art hopper feed elevators are shown in U.S. Pat. No. 3,049,216 issued to Milford A. Campbell, and U.S. Pat. No. 4,860,881 issued to Walter Sticht. The Campbell patent shows a hopper feed elevator which utilizes a housing disposed beneath an opening in a bin containing the parts to be conveyed leaving spaced channels through which lugs on the conveyor may travel. The Sticht patent shows a conveyor belt passing through a bin having cleats on a belt which pass by a gap in the lower portion of the bin.